Abstract: The mode function is the key for obtaining the critical load of astayed steel column. Based on two basic modes, symmetric and anti-symmetric,the basic buckling mode functions are obtained, and three examples areconsidered for the performance of simulation curves by varying their keyparameters. At last, the buckling mode function for asymmetric bucklingis obtained. The results indicate that the engineering requirements canbe met when the number of simulation curves is equal to the total sectionnumber of the stayed steel column.